MEXICO CITY (AP) - The Mexican army said Tuesday it has seized $15.3 million in bundles of cash believed to belong to members of the Sinaloa drug cartel.

Army spokesman Gen. Ricardo Trevilla said soldiers found the piles of U.S. bills inside a car in a downtown neighborhood of the border city of Tijuana late Monday, along with two rifles, two pistols and three kilograms (6.6 pounds) of cocaine.

Trevilla said no arrests were made at the scene, but that soldiers received information that the money was to have been taken to a Tijuana home he described as "the center of financial operations" of the Sinaloa cartel.

Trevilla says it was the second largest money cache found by soldiers. He did not say what led troops to the cash, nor why they believed the money was en route to the house. Nor did he specify the location of the house.

Two carloads of federal police were staked out Tuesday outside a home in an upscale, gated community in downtown Tijuana. The police refused to comment on whether it was the house mentioned in Monday's raid.

The biggest army cash seizure made in Mexico was in September 2008, when troops found $26.2 million in a house in Culiacan, capital of the Pacific coast state of Sinaloa.

The country's biggest cash seizure of any kind occurred in March 2007, when federal police located $207 million in Mexico City believed to be tied to a ring selling pseudoephedrine, the main ingredient in methamphetamine.